package com.hmdp.utils;

import org.springframework.data.redis.core.StringRedisTemplate;
import org.springframework.stereotype.Component;

import javax.swing.text.DateFormatter;
import java.time.LocalDateTime;
import java.time.ZoneOffset;
import java.time.format.DateTimeFormatter;

@Component
public class RedisIdWorker {
    /*
    * 开始时间戳
    * */
    private static final long BEGIN_TIMESTAMP=1698192000L;
    //序列号的左移位数
    private static final int COUNT_BITS=32;

    private StringRedisTemplate stringRedisTemplate;

    public RedisIdWorker(StringRedisTemplate stringRedisTemplate) {
        this.stringRedisTemplate = stringRedisTemplate;
    }

    public long nextId(String keyPrefix){
        //1.生成时间戳
        long nowSecond = LocalDateTime.now().toEpochSecond(ZoneOffset.UTC);
        long timestamp = nowSecond - BEGIN_TIMESTAMP;

        //2.生成序列号
        //2.1 获取当天日期，精确到天
        String date = LocalDateTime.now().format(DateTimeFormatter.ofPattern("yyyy:MM:dd"));
        //2.2 自增长
        Long count = stringRedisTemplate.opsForValue().increment("icr" + keyPrefix + date);
        //3.拼接并返回
        long l = timestamp << COUNT_BITS | count;
        return l;
    }

}
